Apparatus for forming a lining on centrifugal mold



March 31, 1959 P. E. EWING I 2,379,563

APPARATUS FOR FORMING A LINING ON CENTRIFUGAL MOLD Filed March 17, 1958 4 Sheets-Sheet l INVENTOR, P004 5. fly/N6 March 31, 1959 APPARATUS FOR FORMING A LINING ON CENTRIFUGAL MOLD Filed March 1'7, 1958 E. EWING 4 Sheets-Sheet 2 give/V5 5 i March 31, 1959 P. E; EWING APPARATUS F'OR FORMING A LINING ON CENTRIFUGAL MOLD Filed March 17, 1958 4 Sheets-Sheet 3 INVENTOR. E EMA/6 INVENTOR. 1 /704 5 (EM/V6 4 Sheets-Sheet 4 P. E. EWING BY I fi prraeA/a March 31, 1959 Filed March 17, 1958 United States Patent APPARATUS FOR FORMING A LINING ON CENTRIFUGAL MOLD Application March 17, 1958, Serial No. 721,902

13 Claims. (Cl. 22-17) This invention relates to the art of centrifugal casting of metals and is particularly directed to apparatus for lining cylindrical metal flasks with sand to form molds for subsequent production of centrifugal castings. This invention finds particular usefulness in connection with the manufacture of centrifugally cast metal pipe.

It is highly desirable, from the standpoint of economical. production on a quantity basis, to provide means for sand lining flasks in a minimum time per flask. It is also highly desirable that the sand lining operation be accomplished while the flask is in a vertical position in order to secure substantially uniform distribution of sand within the bore of the flask. The present invention satisfies both of these requirements and utilizes a rotary transfer mechanism which receives empty flasks in horizontal position, turns them to an upright position for the sand lining operation, and then returns them to a horizontal position preparatory to the spinning cycle in the casting operation. While the flask is held in a vertical position on the transfer member a pattern is inserted upward into the interior of the flask and a sand delivering mechanism is lowered into contact with the upper end of the flask and pattern. Sand is then blown or otherwise deposited in the annulus between the pattern and the flask. Upon retraction of the pattern and the sand delivery apparatus, the sand lined flask is swung by the transfer member to a horizontal position and it then moves laterally away from the transfer member. Other detailed objects and advantages will appear hereinafter.

In the drawings:

Figure 1 is a side elevation partly in diagrammatic form, showing apparatus for the manufacture of cen-, I trifugally cast pipe and including a preferred embodiment of this invention.

Figure 2 is an end elevation taken substantially on the lines 22 as shown in Figure 1.

Figure 3 is an end elevation taken substantially on the lines 33 as shown in Figure 1.

Figure 4 is a sectional detail taken substantially on the lines 44 as shown in Figure 3.

Figure 5 is a fragmentary side elevation.

Figure 6 is a sectional view partly broken away, taken substantially on the lines 66 as shown in Figure 5.

Figure 7 is a fragmentary side elevation showing a sand lined flask in discharge position.

Figure 8 is a wiring diagram.

Referring to the drawings, the centrifugal casting machine generally designated 10 includes pairs of rollers 11 which are power driven and which serve to spin a cylindrical mold 12 in horizontal position. A centrifugal casting is formed by molten metal introduced into the interior of the spinning mold. The mold 12 comprises a cylindrical metal flask 13 having a. lining of sand. After the casting has solidified within the mold 12, the mold is placed on the track 14 and rolls down to the stripper 2 station generally designated 15. The casting and sand lining are ejected from the mold and the empty flask 13 is then elevated by means of the hydraulic cylinder as- 2,879,563 Patented Mar. 31, 1959 sembly 16 to the position shown in dotted lines at 17. The flasks 13 then roll down the incline 18 and rest on the elevated track 19 leading to the transfer and sand lining apparatus generally designated 20. The present invention is embodied in this apparatus and the apparatus is described below in detail.

As each flask 13 reaches the apparatus 20 from the trackway 19, it is secured to a rotary transfer member 21 and then turned to an upright position. A pattern 22 is moved upward into the interior of the flask 13 by means of the power cylinder assembly 23, and the sand delivery apparatus generally designated 24 is lowered into contact with the upper end of the vertically positioned flask 13. A lining of sand is formed within the flask 13 around the pattern 22. The sand delivery apparatus 24 and the pattern 22 are then retracted away from the flask 13. The rotary transfer member 21 then turns through one-quarter revolution to return the sand filled flask 13 to horizontal position adjacent the upper end of the inclined track 24. The sand lined flask 13 is then released from a rotary transfer member 21 and rolls by gravity on the track 25 toward the centrifugal casting machine 10.,

Proceeding to a more detailed description of the transfer and sand lining mechanism 20, the transfer member generally designated 21 includes a framework fixed on a central horizontal shaft 31. The shaft 31 is sup ported in axially spaced bearings 32 and 33 mounted on pedestals 34. The framework 30 is positioned between the bearings 32 and 33. Four flask-receiving seats 35 are provided on the front face of the framework 30 and each of these seats is defined by spaced pairs of brackets 36 and 37. The inclined brackets 36 each cooperate with one of the V brackets 37 respectively to contact a cylindrical portion of a metal flask 13. Each flask 13 is provided with an end flange 38 at each end and these end flanges engage shoulders 39 and 40 provided on the brackets 36 and 37 respectively to prevent endwise movement of the flask 13 relative to the framework 30. The V brackets 37 are mounted closer to the shaft 31 than the inclined brackets 36 so that the flask 13 at the loading station 41 adjacent the lower end of the track 19 rests on the V brackets 37.

Means are provided for retaining the flask 13 on the seat 35 and as shown in the drawings, this means includes a plurality of electro-magnets 42. These magnets are arranged in pairs, one adjacent each pair of brackets 36 and 37. When the magnets are energized electrically, they serve to hold adjacent metal flasks 13 in position between the pairs of brackets 36 and 37 and to prevent movement of the flask away from the front face of the framework 30. Direct current is delivered to the magnets 42 through slip rings 43 mounted on the shaft 31. A switch 44 is provided for each pair of magnets and this switch is normally closed. Means are provided for opening the switch associated with the magnets adjacent the discharge position 45 at the upper end of the trackway 25 Opening of the switch de-energizes the magnets and permits the sand filled flask 13 to roll downward by gravity along the inclined brackets 36 and onto the upper end of the trackway 25.

Means are provided for lining each flask 13 with sand when the flask 13 is in the vertical filling station shown in Figure 2. As shown in the drawings, this means includes the vertical pattern 22 mounted on the upper end of a piston rod 47 extending from the power cylinder assembly 23. When the rod 47 is projected upward, the pattern 22 moves longitudinally into the bore 49 of the vertical flask 13 to assume the position shown in phantom lines. A sealing plate 50 mounted on springs 51 carried on the cross-head 52 engages the lower end of 1) the flask '13. The cross-head 52 is fixed on the piston rod 47.

The sand delivery device generally designated 24 is conventional in form and is mounted for vertical sliding movement on the frameparts '53 and 54. The lower end of this device 24 comprises a discharge nozzle 55 provided with sealing flange 56 adapted to rest against the upper end of the flask 13. A pilot 57 extends into the upper end of the bore 49, and telescopes into the upper end of the pattern 22 to hold it in central position, and forms a part of the pattern. A shuttle valve plate 60 has been previously actuated by the power cylinder assembly 61 to admit a charge of sand into the chamber 62. After closing the plate, air under pressure from the tank 63 is delivered through va'lve means (not shown) into the chamber 62 to cause the sand 'to be blown through ring apertures 64 in the nozzle '55. The sand "passes 'into the annular'space between the pattern 22 and thetbore 49 of the flask 1-3 and fills the space with sand at substantially uniform density.

The sand blowing device 24 is then retracted in an upward direction by means of the power cylinder assemblies 65 and the pattern 22 is withdrawn downward by means of the power cylinder assembly 23. The transfer member 21 is then turned about the shaft axis 31 to bring the sand filled flask 13 to horizontal position at the discharge station 45. The weight of the sand filled flask assists this turning movement, since it is not counterbalanced by any flask on the opposite side of the transfer member 21. A marking device generally designated 70 is then employed to impress suitable indicia into the bore 71 of the sand lining 72. This marking device 70 may be of conventional form and includes the cam operated marking lugs 73 which are moved axially into the bore 71 from one end then expanded radially to form depressions in the sand lining 72. (Molten metal subsequently fills these depressions, producing raised indicia on the finished casting.) The device 70 is then withdrawn axially and this withdrawal movement may be utilized to actuate the switch '44. The switch 44 controlling the magnets 42 adjacent the discharge station 45 is then actuated to de-energize the magnets and permit the sand filled flask to roll by gravity down its inclined brackets 36 to the trackway 25.

Means are provided for turning the transfer member 21 about the axis of the shaft 31, and as shown in the drawings this means includes a power cylinder assembly 75 pivoted at one end to the stationary beam 76 and acting'through'piston rod 77 to actuate crank arm 78. A device 79 and pivot pin 80 connect-the rod 77 to the crank arm'78. A one-way overrunning clutch 81 conmeets "the crank arm '78 in "driving relationship in the 'shaft'31. 'A drag'brake '82 provides a frictional restraint impeding'turning movement'df the shaft31. When the power cylinder "assembly 75 is actuated to retract the rod 77, the crank arm 78 transmits torque to the shaft 31 through theone-way clutch 81. The proportions of the parts are such that the stroke of the power cylinder assembly 75 is adequate to'turn the transfer member 21 through one-quarter revolution. When the power cylinder assembly 75 is actuated to extend the rod 77, the arm 78 is-moved in a clockwise direction as viewed in Figurei3 but themotion is not-transmitted to theshaft '31 since the one-way clutchSl transmits motion only in the other direction.

Means are providedi'for latching the transfer member 21 in any one of four positions and as shown inthe drawings, this means includes 'four latching lugs 83 mounted centrally with respect to each of the seats 35.

Each of theselugs 83 is provided with a central slot 84 for reception of a reciprocablellatch bar 85 operated by 'power cylinder 'assemb1y186. The hydraulic connections for the power'cylinder'assemblies 86 and'75 are inter- "locked so'that the latch bar 85 is released before the rod 4, 77 can be retracted to cause turning movement of the transfer member 21.

Having fully described my invention, it is to be understood that I do not wish to be limited to the details herein set forth, but my invention is of the full scope of the appended claims.

I claim:

1. Apparatus for lining flasks with sand to form molds for centrifugal castings, comprising in combination: a transfer member mounted to turn about a certain axis, the transfer member having a plurality of circumferentially spaced flask-receiving seats each defined by flaskcontacting elements on the transfer member, the elements comprising the seats being shaped to support a plurality of flasks with their respective longitudinal axes lying in a common plane normal to the axis of the transfer member, means for turning the transfer member by increments corresponding to spacing of the seats, means to deliver flasks horizontally to the transfer member at a loading station, means at a second station for lining a flask with sand while the flask'is supported on the transfer member, and means at a third station to discharge sandlined flasks horizontally from the transfer member.

2. Apparatus for lining flasks with sand to form molds for centrifugal castings, comprising in combination: a transfer member mounted to turn about a horizontal axis, the transfer member having a plurality of circumferentially spaced flask-receiving seats each defined by flaskcontacting elements on the transfer member, the elements comprising the seats being shaped to support a plurality of flasks with their respective longitudinal axes lying in a common plane normal to the horizontal axis of the transfer member, means for turning the transfer member by increments corresponding to the spacing of the seats, means to deliver flasks horizontally to the transfer member at a loading station, means at a second station for lining a flask with sand while the flask is supported in vertical position on the transfer member, and means at a third station to discharge sand-lined flasks horizontally from the transfer members 3. Apparatus for lining flasks with sand to form molds for centrifugal castings, comprising in combination: a transfer member mounted to turn about a horizontal axis, the transfer member having four circumferentially spaced flask-receiving seats each defined by flask-contacting elements on the transfer member, the elements comprising the seats being shaped to support a plurality of flasks with their respective longitudinal axes lying in a common plane normal to the horizontal axis of the transfer member, means for turning the transfer member by onequarter turn increments, means to deliver flasks horizontally to the transfer member at a loading station, means at a second station for lining a flask with sand while the flask is supported in vertical position on the transfer member, and means at a third station to discharge sand-lined flasks horizontally from the transfer member.

4. Apparatus for lining cylindrical flasks with sand to form molds for centrifugal castings, comprising in combination: a transfer member mounted to turn about a horizontal axis, the transfer member having four circumferentially spaced flask-receiving seats each defined by flask-contacting elements on the transfer member, the elements comprising the seats being shaped to support a plurality of cylindrical flasks with their respective longiflasks horizontally from the transfer member at a low elevation.

5. Apparatus for lining cylindrical metal flasks with sand to form molds for centrifugal castings, comprising in combination: a transfer member mounted to turn about a horizontal axis, the transfer member having circumferentially spaced flask-receiving seats each defined by flask-contacting elements on the transfer member, the elements comprising the seats being shaped to support a plurality of cylindrical flasks with their respective longitudinal axes lying in a common plane normal to the r horizontal axis of the transfer member, means for turning the transfer member by increments corresponding to spacing of the seats, electro-magnets on the transfer member associated with each of said seats for retaining the metal flasks in contact with said elements, means to deliver flasks horizontallyto the transfer member at a loading station, means at a second station for lining a flask with sand while the flask is supported in vertical position on the transfer member, and means at a third station to discharge sand-lined flasks horizontally from the transfer member, upon de-energizing of electromagnets adjacent said third station.

6. Apparatus for lining cylindrical metal flasks with sand to form molds for centrifugal castings, comprising in combination: a rotary transfer member having a plurality of circumferentially spaced flask-receiving seats, thereon, the seats being positioned to support a plurality of cylindrical flasks with their respective longitudinal axes lying in a common plane normal to the axis of the transfer member, means for turning the transfer member by increments corresponding to spacing of the seats, electro-magnets on the transfer member associated with each of said seats for retaining the metal flasks in contact therewith, means to deliver flasks horizontally to the transfer member at a loading station at a high elevation, means at a second station for lining a flask with sand while the flask is supported in vertical position on the transfer member, and means at a third station to discharge sand-lined flasks horizontally from the transfer member at a low elevation upon de-energrzing of electro-magnets adjacent said third station.

7. Apparatus for lining cylindrical flasks with sand to form molds for centrifugal castings, comprising in combination: a transfer member mounted to turn about a horizontal axis, the transfer member having circumferentially spaced flask-receving seats each defined by flask-contacting elements on the transfer member, the elements being shaped to support a plurality of cylindrical flasks with their respective longitudinal axes lying in a common vertical plane, means for turning the transfer member, and means for lining a flask with sand while the flask is supported in vertical position on the transfer member, said means including a retractable pattern mounted for upward movement into the interior of the said flask, and a retractable sand delivery device mounted for downward movement to contact the upper end of said flask.

8. Apparatus for lining cylindrical metal flasks with sand to form molds for centrifugal castings, comprising in combination: a transfer member mounted to turn about a horizontal axis, the transfer member having circumferentially spaced flask-receiving seats each defined by flask-contacting elements on the transfer member, the elements being shaped to support a plurality of cylindrical flasks with their respective longitudinal axes lying in a common vertical plane, means for turning the transfer member, electro-magnets on the transfer member associated with each of said seats for retaining the metal flasks in contact with said elements, and means for lining a flask with sand while the flask is supported in vertical position on the transfer member, said means including a retractable pattern mounted for upward movement into the interior of the said flask, and a retractable sand delivery device mounted for downward movement to con tact the upper end of said flask.

9. Apparatus for lining cylindrical flasks with sand esvases castings, comprising in member having circumferentially spaced flask-receiving seats, each seat being defined by pairs of flask-contacting brackets, each pair of said brackets including an inclined bracket and a spaced V bracket cooperating to receive a portion of a flask therebetween, said brackets being mounted upon the transfer member and adapted to support a plurality of cylindrical flasks with their respective longitudinal axes lying in a common plane normal to the axis of the transfer member, means on the transfer member associated with each of said seats for retaining the flasks in contact with said brackets, means to deliver flasks horizontally to the transfer member at a loading station to rest on spaced V brackets, means to turn the transfer member, means at a second station for lining a flask with sand while the flask is supported in vertical position on the transfer member, the flasks being adapted to roll down the inclined brackets by gravity at a third station to discharge sand-lined flasks horizontally from the transfer member, upon release of the retaining means adjacent said third station.

10. Apparatus for lining cylindrical metal flasks with sand to form molds for centrifugal castings, comprising in combination: a rotary transfer member having circumferentially spaced flask-receiving seats, each seat being defined by pairs of flask-contacting brackets, each pair of said brackets including an inclined bracket and a spaced V bracket cooperating to receive a portion of a flask therebetween, said brackets being mounted upon the transfer member and adapted to support a plurality of cylindrical flasks with their respective longitudinal axes lying in a common plane normal to the axis of the transfer member, electro-magnets on the transfer member associated with each of said seats for retaining the metal flasks in contact with said brackets, means to deliver flasks horizontally to the transfer member at a loading station to rest on spaced V brackets, means to turn the transfer member, means at a second station for lining a flask with sand while the flask is supported in vertical position on the transfer member, the flasks being adapted to roll down the inclined brackets by gravity at a third station to discharge sand-lined flasks horizonal- 1y from the transfer member, upon deenergizing of electro-magnets adjacent said third station.

11. Apparatus for lining flanged cylindrical flasks with sand to form molds for centrifugal castings, comprising in combination: a rotary transfer member having circumferentially spaced flask-receiving seats, each seat being defined by pairs of flask-contacting brackets, each pair of said brackets including an inclined bracket and a spaced V bracket cooperating to receive a cylindrical portion of a flask therebetween, the brackets having side faces contacting flanges on the flasks to prevent end-wise movement of the flasks, said brackets being mounted upon the transfer member and adapted to support a plurality of cylindrical flasks with their respective longitudinal axes lying in a common plane normal to the axis of the transfer member, means on the transfer member associated with each of said seats for retaining the flasks in contact with said brackets, means to deliver flasks horizontally to the transfer member at a loading station to rest on spaced V brackets, means to turn the transfer member, means at a second station for lining a flask with sand while the flask is supported in vertical position on the transfer member, the flasks being adapted to roll down the inclined brackets by gravity at a third station to discharge sand-lined flasks horizontally from the transfer member, upon release of the retaining means adjacent said third station.

12. Apparatus for lining flanged cylindrical metal flasks with sand to four molds for centrifugal castings, comprising in combination: a rotary transfer member having circumferentially spaced flask-receiving seats, each seat being defined by pairs of flask-contacting brackets, each pair of said brackets including an inclined bracket and a spaced V bracket cooperating to receive a cylindrical portion of a flask therebetween, the brackets having side faces contacting flanges on the flasks to prevent end-wise movement of the flasks, said brackets being mounted upon the transfer member and adapted to support a plurality of cylindrical flasks with their respective longitudinal axes lying in a common plane normal to the axis of the transfer member, electro-magnets on the transfer member associated with each of said seats for retaining the metal flasks in contact with said brackets, means to deliver flasks horizontally to the transfer member at'a loading station to rest on spaced V brackets, means to turn the transfer member, means at a second station. for lining a flask with sand while the flask is supported in vertical position on the transfer member, the flasks being adapted to roll down the inclined brackets by gravityat a third station to discharge sand-lined flasks horizontally from the transfer member, upon de-energizing of electromagnets adjacent said third station.

13. Apparatus for handling flanged cylindrical flasks, comprising in combination: a rotary transfer member having circumferentially spaced flask-receiving seats, each (3* seat being defined by pairs of flask-contacting brackets, each pair of brackets including an inclined bracket and aspaced V bracket cooperating to receive a cylindrical portion of a flask therebetween, the brackets having side faces contacting flanges on the flasks to prevent endwise movement of theflasks, said brackets being mounted upon" the transfer'member tosupport a plurality of cylindrical flasks with their respective longitudinal axes lying in'a common plane normal to the axis of the transfer member, means for turning the transfer member, certain of the V brackets supporting a flask horizontally at a loading station, and certain of the inclined brackets permitting rolling of another flask horizontally away from the transfer member at a discharge station.

ReferenceSCited in the file of'this patent UNITED STATES PATENTS 2,706,319 Lacey et a1 Apr. 19, 1955 FOREIGN PATENTS 182,399 Germany Mar. 14, 1907 233,044 Germany Apr. 1, 1911 310,510 Great Britain June 18, 1930 

